Runners, out East, can be blue (5)
I believe the answer is:
skies
'runners out east can be blue' is the definition.
I can't judge whether this definition defines the answer.
'runners out east' is the wordplay.
'runners' becomes 'skis' (ski is a kind of runner).
'out' is an insertion indicator.
'east' becomes 'e' (abbreviation).
'skis' going around 'e' is 'SKIES'.
Can you help me to learn more?
(Other definitions for skies that I've seen before include "Heavens" , "Hits high in the air" .)